fix(vet): report an error when a query is unpreparable, close prepare…

…d statement connection (#2486)

internal/cmd/vet.go

@@ -34,6 +34,17 @@ var ErrFailedChecks = errors.New("failed checks")
 const RuleDbPrepare = "sqlc/db-prepare"
 const QueryFlagSqlcVetDisable = "@sqlc-vet-disable"
 
+type emptyProgram struct {
+}
+
+func (e *emptyProgram) Eval(any) (ref.Val, *cel.EvalDetails, error) {
+       return nil, nil, fmt.Errorf("unimplemented")
+}
+
+func (e *emptyProgram) ContextEval(ctx context.Context, a any) (ref.Val, *cel.EvalDetails, error) {
+       return e.Eval(a)
+}
+
 func NewCmdVet() *cobra.Command {
 	return &cobra.Command{
 		Use:   "vet",
@@ -53,17 +64,6 @@ func NewCmdVet() *cobra.Command {
 	}
 }
 
-type emptyProgram struct {
-}
-
-func (e *emptyProgram) Eval(any) (ref.Val, *cel.EvalDetails, error) {
-	return nil, nil, fmt.Errorf("unimplemented")
-}
-
-func (e *emptyProgram) ContextEval(ctx context.Context, a any) (ref.Val, *cel.EvalDetails, error) {
-	return e.Eval(a)
-}
-
 func Vet(ctx context.Context, e Env, dir, filename string, stderr io.Writer) error {
 	configPath, conf, err := readConfig(stderr, dir, filename)
 	if err != nil {
@@ -100,7 +100,7 @@ func Vet(ctx context.Context, e Env, dir, filename string, stderr io.Writer) err
 	}
 
 	checks := map[string]cel.Program{
-		RuleDbPrepare: &emptyProgram{},
+		RuleDbPrepare: &emptyProgram{}, // Keep this to trigger the name conflict error below
 	}
 	msgs := map[string]string{}
 
@@ -198,7 +198,8 @@ type dbPreparer struct {
 }
 
 func (p *dbPreparer) Prepare(ctx context.Context, name, query string) error {
-	_, err := p.db.PrepareContext(ctx, query)
+	s, err := p.db.PrepareContext(ctx, query)
+	s.Close()
 	return err
 }
 
@@ -316,12 +317,15 @@ func (c *checker) checkSQL(ctx context.Context, s config.SQL) error {
 					continue
 				}
 				original := result.Queries[i]
-				if prepareable(s, original.RawStmt) {
-					name := fmt.Sprintf("sqlc_vet_%d_%d", time.Now().Unix(), i)
-					if err := prep.Prepare(ctx, name, query.Text); err != nil {
-						fmt.Fprintf(c.Stderr, "%s: %s: %s: error preparing query: %s\n", query.Filename, q.Name, name, err)
-						errored = true
-					}
+				if !prepareable(s, original.RawStmt) {
+					fmt.Fprintf(c.Stderr, "%s: %s: %s: error preparing query: %s\n", query.Filename, q.Name, name, "query type is unpreparable")
+					errored = true
+					continue
+				}
+				name := fmt.Sprintf("sqlc_vet_%d_%d", time.Now().Unix(), i)
+				if err := prep.Prepare(ctx, name, query.Text); err != nil {
+					fmt.Fprintf(c.Stderr, "%s: %s: %s: error preparing query: %s\n", query.Filename, q.Name, name, err)
+					errored = true
 				}
 				continue
 			}